A chemically amplified resist composition used for semiconductor microfabrication employing a lithography process contains a resin which contains a structural unit having an acid-labile group and which itself is insoluble or poorly soluble in an alkali aqueous solution but becomes soluble in an alkali aqueous solution by the action of an acid, and an acid generator comprising a compound generating an acid by irradiation.
In semiconductor microfabrication, it is desirable to form patterns having high resolution and good line edge roughness, and it is expected for a chemically amplified resist composition to give such patterns.
US 2006-0194982 A1 discloses a chemically amplified resist composition containing the salt represented by the following formula:

wherein E represents a hydrogen atom or a hydroxyl group, and a resin which contains a structural unit having an acid-labile group and which itself is insoluble or poorly soluble in an alkali aqueous solution but becomes soluble in an alkali aqueous solution by the action of an acid.
US 2007-27336 A1 discloses a chemically amplified resist composition comprising the salt represented by the following formula:
and a resin which contains a structural unit having an acid-labile group and which itself is insoluble or poorly soluble in an alkali aqueous solution but becomes soluble in an alkali aqueous solution by the action of an acid.
US 2003/0194639 A1 also discloses a chemically amplified resist composition containing the salt represented by the following formula:
as the acid generator.